Double diode



G. F. ELSTON DOUBLE DIODE Nov. 21, 1939..

Filed March 51, 1938 INVENTOR- GEORGE 1-7 ELSTON. BY

ATTORNEY.

Patented Nov. 21, 1939 'UNETEE STATES? DOUBLE DIODE George Elston,Bloomfield, N. J., assignor, by mcsne assignments, to Radio Corporationof America, Delaware New York, N. Y., a corporation of Application March31, 1938, Serial No. 199,138

1 Claim. My invention relates to electron discharge devices and moreparticularly to electrode assemblies and their supporting means withinthe tube.

The object of my invention is to provide an electrode assembly of theunit mount construction which is easy to assemble, rugged inconstruction, and has good electrical characteristics. The electrodes ofmy improved tube comprise two diode units mounted in a single unitarystructure that is easy to assemble and mount in the envelope, and inwhich the spacing between cathode and anode remains constant duringhandling and use.

My invention is defined with particularity in the appended claim but oneembodiment thereof is described in detail in the following specificationand accompanying drawing in which:

Figure 1 is a perspective view of an electron discharge device embodyingmy invention, and

Figure 2 is a detail view of an anode constructed according to myinvention.

The mount shown in Figure 1, which is particularly adapted for a metalenvelope, comprises a metal stem or header with electrode lead-in wires2 sealed gas-tight in a glass disc or button 3 closing the centralportion of the header. The electrode assembly comprises two parallel"insulating spacers 4, such as sheets of mica, perforated withregistering openings to receive and support in insulated spaced relationanodes 5, cathodes 6, preferably of the indirectly heated type, and atransverse shield I. The anodes are attached at their ends to theinsulating spacers and are held in concentric spaced relation to theirrespective cathodes. When assembled, the electrodes are attached,preferably by welding, to lead-in conductors 2, a metal shell is placedover the electrode and welded along its rim to the metal header I, andthe envelope is degassed, sealed-ofl and attached to a conventionalbase.

Each anode 5 is cylindrical and has a longitudinal flange H3. The anodemay conveniently be made of an oblong sheet of metal, such as nickel,pressed across the middle to form a tubular portion or cylinder, withthe end portions of the sheet forming two flap-s 8 which are broughttogether and spot welded to make the longitudinal flange m. The flangeill may, if desired, be slightly longer than the tubular portion of theanode to project beyond the ends of the anode and provide clearancebetween the ends of the anode and the spacers. The flange may bestiffened by ribs or channels pressed lengthwise along the flange. Theends of flange ID are formed with ears or tabs 1 I integral with theflaps ditionally strengthened and 8. The cars are inserted throughperforations in the spacers and when spread as shown in Figure 1 drawthe spacers into snug engagement with ends of the flanges of the twoanodes. The two flaps 8 forming the longitudinal flange I0 are bentperpendicular to the plane of the flange to form fins i2 and areprovided at their ends near their outer edges with lugs l3 for engagingthe spacers a substantial distance from the plane of the flange. Theears ll hold the spacers in snug engagement with the ends of the flangel0 and fins 2 to prevent tilting of the spacer and the lugs l3effectively prevent rotation of the flange about an axis through theears II. To insure firm attachment of the anode to the spacer, thedistance between lugs I 3 may be made slightly less than the width ofthe spacer so that the edges of the lugs may cut into the edges of thespacer. These two points by contact, cooperating with the third point ofcontact at ear ll, secure the parts together. The assembly is adthediode units are electrically shielded by the transverse shield orpartition 1, preferably of metal, inserted at its ends in perforationsin the spacers.

An electrode assembly constructed according to my invention is easy toassemble, is rugged in construction, has good electricalcharacteristics, and is inexpensive to make. The reduced number of partsminimize cost and facilitate assembly of my improved device. The usualanode side rods and anode-to-spacer straps are eliminated. Longitudinalflange It with the perpendicular fins l2 are particularly rigid and areadapted, with the ears H and lugs Hi, to prevent movement of the spacersor anodes. The ears H at one end of the anodes are inserted in onespacer and the cathodes are placed in the anodes and one end inserted inperforations coaxial with the anodes, shield 9 is put in place, and thesecond insulating spacer is pressed into place. To look the assembly ina rigid unitary structure it is merely necessary to bend or spread theears H at the ends of the flanges. The assembly may then be placed onthe header and the appropriate conductors secured, as by welding, to theelectrodes.

Since many modifications may be made in an electrode assemblyconstructed according to my invention without departing from the scopethereof, it is desired that my invention be limited only by the priorart and by the appended claim.

I claim: v A unitary electrode assembly for electron discharge devicescomprising a pair of parallel inend of said flange integral with theflaps extending through an opening in the spacers and a lug extension oneach end of each fin, the lug extensions at one end of the fins being onopposite sides of and removed from the plane of said flange, and theedges of the lugs engaging opposite edges of the spacer, the distancebetween the edges of the lugs being slightly less than the width of thespacer between the lugs.

GEORGE F. ELSTON.

